Added by Gary Dunn on October 8, 2012
A newly discovered asteroid, called 2012 TV, passed by Earth at approximately 15:00UT/GMT on Sunday at a distance of 255,000km from Earth – about 0.66 LD – the distance between the Earth and Moon (the average distance between the Moon and Earth is 150m km)..
The asteroid is about 40m across and reached a magnitude of approximately 13.5 – approximately 700 times fainter than the brightness of space objects that can be seen with the unaided eye. The maximum brightens (apparent magnitude) of the Moon is -12.92.
The minimum distance of the asteroid is considered to be very close yet its small size of 40m does not make it a Potentially Hazardous Asteroid – an asteroid having a brightness of 22 or less (less is brighter), larger than 100m, and closer than 7.4m km from Earth.
Potentially Hazardous Asteroids (PHAs) have the potential to impact the earth and are closely monitored by scientists. The data from PHAs are used to predict close-approach objects and their threat of impact with the Earth.
The next approach of a Near Earth Object is expected to be on October 12 when asteroid 2012TC4, about 22m in size, will pass within 0.2 LD – this is also not considered to be a PHA.
Objects like asteroids and space rocks that measure between 5-10m impact the Earth about one each year – with most vaporizing or exploding in the upper atmosphere. 1km sized objects impact the Earth about once ever 1 million years and 5km or larger objects impact the Earth about once every 10 million years.